Microscope



y 1940- v G. B. GALLASCH ET AL 2,208,839

MICROSCOPE Filed Dec. 7, 1935 Mix GMKO Patented July 23, 1946 UNITED STATES PATENT cFricE MICROSCOPE Application December 7, 1935, Serial No. 244,438

3 Claims.

I The present invention relates to microscopes and more particularly to mechanisms for obtaining fineadjustments of focus. 7

One of the objects of the present invention is to provide a new and improved fine adjustment for microscopes. Another object is to provide a microscope in which the operating knob for the fine adjustment is located adjacent the base. A further object is to provide a microscope having a low position fine adjustment without weakening the microscope arm. These and other objects and advantages reside in certain novel features of construction, arrangement and combination of parts as will hereinafter be more fully set forth and pointed out in the appended claims.

Referring to the drawing:

Fig. 1 is a vertical section with parts in elevation, showing our new microscope.

.Fig. 2 is an enlarged fragmentary vertical section of the fine adjustment actuating mechanism. Fig. 3 is a section taken on line 33 of Fig. 1. Fig. 4 is a section taken on line 4-4 of Fig. 2.

One embodiment of our invention is illustrated in the drawing wherein l0 designates a base having twoupstanding projections II and i2 spaced apart to receive the microscope arm l3. These projections l] and 12 are formed with aligned bearing apertures l4 and I5, respectively. A recess I6 is formed in the projection ll around the, aperture [4 and a similar recess I! is formed in the projection [2 around the aperture IS. The microscope arm [3 is hollow and has aligned openings [8 in its side walls in alignment with the openings I4- and [5 of the projections I l and l2.

A hollow cylindrical bushing l9 extends through the openings l4, l5 and I8 and forms a bearing on which the arm [3 pivots relative to the base l0. Two washers 20 and 2| are placed on this bushing 19 between the arm I3 and the projections II and 12.

One end of the bushing i9 is formed with an enlarged head or flange 22 which fits within the recess [6 and bears against a washer 23. The other end of the bushing 19 is threaded at 2A and is provided with a key slot 25. A washer 26 fits over the bushing l9 within the recess l1 and is held against rotation relative to the bushing by a key 21 which engages in the slot 25. A nut 28 is threaded on the portion 24 of the bushing l9 and engages the washer 26 to secure the bushing i9 in the projections H and [2. This nut 28 is transversely slotted at 29 and a screw 3|! is threaded through one side of the slot to spread the nut 28 and lock it securely on the bushing I9.

52 in the arm l3 by a set screw53.

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not i are A shaft 3! extends longitudinally through the bushing i9 and is journalled at one end in the end wall 32 thereof. The central portion of this shaft 3| is threaded-as indicated at 33 and a travelling nut 34 is threaded on this portion of the shaft. A slot Hi extends longitudinally through the side wall of the bushing l9 and the walls of this slot engage the sides of the nut 34 to hold it against rotation with the shaft 3!. Thus, rotation of the shaft 3! will cause longitu dinal movement of the nut 38 and the limits of this movement are determined by lugs 35 onthe shaft 35 which are engaged by projections 36 on the nut 3 upon predetermined travel of the nut.

The other end of the shaft 3i is journalled in a bearing member 37 which is secured to the head or'flange 22 by suitable screws or bolts 38 and a flange 39 on the shaft'3l engages'in a recess til in the bearing 3'! to prevent 'longitudinal'movement of the shaft 3!. The shaft 3! may be rotated by knobs ii and 52 secured on its ends by screws or bolts 33 and M, respectively. The knob M is keyed to the shaft 3! by a screw t5 which extends into a key slot 46 .in the shaft 3!. This knob M has a skirt Al upon which are index marks, not shown, to cooperate with index ester marks, not shown, on the flange 48 of the bearing member 3i. These two sets of index marks co operate to indicate the extent of movement of the fine adjustment as is known in the art.

The rear wall of the tubular arm 13 above the bushing l9 has a projection 49 for receiving one end of a shaft 58. The other end of this shaft is held in a bushing 5! which is secured in a hole This set screw preferably goes through the bushing 5| and engages the shaft 50 although the shaft 5t may, of course, be free to turn.

A plate 56 is journalled on the shaft 56 and has a depending leg 55, the end 56 of which is formed to bear against aprojection 57 on the nut 34 so that movement of the nut 34 will cause rocking movement of the plate 54 on the shaft 5!. A conical depression 53 is formed at the rear end of the plate 54 out of alignment with the shaft 50. The bearing point 59 of a rigid link 60 rests in this depression v53 so that the plate 54 and leg 55 form a bell crank lever for trans-- mitting motion from the nut 3G to the link 5.

This rigid link 60 is so shaped that it can be dropped into the hollow arm i3 through the opening 6i at the top of the arm. Such a shape permits the arm Hi to. be cast or otherwise formed as a single, unitary tube and hence makes the arm quite strong and rigid against forces which would otherwise cause the arm to bend or twist. A screw 62 extends through the rear wall of the arm I3 and engages in a groove 63 in the link to hold the link 60 against turning and to prevent the link 60 from rubbing against the sides of the arm [3.

A block 64 is slidably mounted on the arm l3 over the opening 6i and carries a projection 65 which extends into the hollow of the arm I3. A pin 66 fixed to the projection rests on top of the link 68 and a suitable coil spring 61 urges the projection 65 toward the link 60. The motion of the link 89 is thus directly transmitted to the block 6 3.

A microscope body tube 68 carrying an objective 69 and eyepiece H1 is slidablymounted on the block 64 and may be moved relative to the block by a rack and pinion mechanism, not shown, under the control of the coarse adjustment knob II as is well known in the art.

One of the chief features of our improved microscope is the fact that it is simple to assemble and yet dust-proof and strong after assembly is complete. The lower end of the arm i3 is provided with an opening 12 through which the plate 54 and leg 55 can be inserted and this opening, together with the hole are completely closed and made dust-tight by the stage 13 or substage assembly, not shown, which may be secured on the arm I3 directly over these apertures.

The fine adjustment screw 33, nut 34 and bushing I9 may be completed as a sub-assembly before insertion in the openings M, 55 and 18. After insertion, the bushing I9 is locked relative to the arm [3 by a screw M which extends through the arm 13 and engages in a hole iii in the bushing 19. In this way, the bushing i9 is made to turn with the arm so that there is no disturbance of the fine adjustment setting when the arm 53 is pivoted relative to the base iii.

From the foregoing, it will be apparent that we are able to attain the objects of our invention and provide a microscope having a low position fine adjustment and a hollow tubular arm through which the movement is transmitted to the body tube. Various modifications of structure can, of course, be made without departing from the spirit of our invention or the scope of the appended claims.

We claim:

1. In a microscope, a base, a one-piece, curved, tubular arm carried by said base and extending upwardly and forwardly therefrom, a microscope fine adjustment mechanism within and extending across said arm adjacent said base, a shaft fixed within said arm above and perpendicular to said mechanism, a bracket pivotally mounted on said shaft and extending from the front to the rear within said arm, a depending leg on the front end of said bracket operatively engaging said mechanism for actuation thereby, said bracket having a depression in its top surface adjacent its rear end and out of alignment with said shaft, a curved, rigid link extending upward within said tubular arm, a pivot point on the lower end of said link engaging in said depression, said link having a depression at its upper end, a microscope body tube assembly vertically slidably mounted at the upper end of said arm, a projection on said assembly projecting into said tubular arm, and a downwardly extending pin on said projection engaging in the depression on said link.

2. In a microscope the combination of a base, a one piece tubular arm mounted on said base and extending in a curve rearwardly and upwardly and then forwardly therefrom, the upper end of said arm lying in a substantially vertical plane and being provided with an enlarged opening, a block providing a lens tube holder slidably mounted on the upper end of said arm, said block having a projection forming a support member, a second support member movably mounted within said arm, said support members and link being provided with cooperating depres' sions and pivot pins supporting said link between pivot points at its upper and lower ends, and a line adjustment mechanism having a ro-' tatable shaft extending through said arm-near the bottom thereof for moving said second men-' tioned support member, said link being curved so that it is freely passable through said open- 3. In a microscope thecombination of a base, a one piece tubular arm mounted on said base and extending in a curve rearwardly and upward-1y and then forwardly therefrom, the upper end of said arm lying in a substantially vertical plane and being provided with an enlarged opening, a block providing a lens tube holder slidably mounted on the upper end of saidarm, said block having a projection forming a support member, a second support member movably mounted within said arm, said support members and link being provided with cooperatingdepressions and pivot pins supporting said link between pivot points at its upper and lower ends; a fine adjustment mechanism having a rotatable shaft extending through said arm near the bottom thereof for moving said second mentioned support member, and means extending through the wall of said arm and engaging said-'link'for maintaining the link out of contact with the interior of the arm and in fixed position relative to rotational movement upon its pivots, said link being so curved that it is freely passab through said opening.

GEORGE B. G'rALLASCH. HENRY F. KURTZ. CARL H. O. WI'I'I'IG. 

